Substantive hydrophobic cationic UV-absorbing compounds

ABSTRACT

Substantive UV absorbing organic-soluble quaternary salts of cinnamidoalkylamine are described. Hair, skin and fabric care compositions containing the compounds of formula I.  
                 
 
     wherein  
     R 1  is a substituent, selected from H, halo, —OH, —NH 2 , —NO 2 , —OCH 3 , —N(CH 3 ) 2 , alkyl groups containing from 1 to 6 carbon atoms, alkoxy groups containing from 1 to 6 carbon atoms, alkylamino or N,N-dialkylamino groups containing from 1 to 6 carbon atoms;  
     R 2  is selected from hydrogen, alkyl group containing from 1 to 12 carbon atoms;  
     R 3  and R 4  are independently selected from benzyl, alkyl group containing from 1 to 12 carbon atoms,  
     n is an integer from 1 to 6;  
     R 5  is selected from an alkyl group containing from 8 to 22 carbon atoms; alkenyl groups containing from 8 to 22 carbon atoms;  
     R 7  is selected from bromo, chloro, nitro, methyl and ethyl groups.

FIELD OF INVENTION

[0001] The invention relates to substantive hydrophobic cationicUV-absorbing compounds. More particularly, the invention relates tonovel, cationic, non-hydrolysable, non-irritating UV-absorbingbis-quaternary salts of cinnamidoalkylamines which are substantive tofabric, skin and hair. The invention also relates to a process ofmanufacture of the said compounds and further to their use in hair, skinand fabric care formulations.

BACKGROUND AND PRIOR ART

[0002] The harmful effects of solar UV-radiation on skin are well known.The UV-B (290-320 nm) portion of solar spectrum is largely responsiblefor erythema (sunburn) and cancer. [M. M. Rieger, Cosmet. Toiletries,102 (3), 91, (1987); L. Taylor, Skin Cancer Foundation J., 4, (90)(1986)].

[0003] Similarly, photodegradative effect of UV-radiation on human hairis well documented. Continuous exposure to sunrays lightens hair colorand makes human hair rough, brittle and difficult to comb. UV rays arereported to damage the proteins of cuticles. Prolonged irradiationresults in diminished tensile strength due to breaking of disulphidebonds in keratin. [R. Beyak et al, J. Soc. Cosmet. Chem. 22, 667-668(1971), E. Hoting et al, J. Soc. Cosmet. Chem. 46, 85-99 (1995)].

[0004] In addition, UV light is also known to fade colored garments. [P.C. Screws, Text. Chem. Color, 11, 21 (1987); B. Milligan et al, Polym.Degrad. Stab. 10 (4), 335 (1985)].

[0005] A number of UV-absorbing compounds like derivatives of salicylicacid, benzophenones, benzotriazoles, cinnamic acid have been used inpersonal care products. However, all these molecules suffered from amajor disadvantage of lack of substantivity. To make this UV-absorbingmoieties more substantive, structural modification have been introduced.U.S. Pat. No. 5,427,773 (1995) discloses cationic substantivephotofilters based on dimethylamino benzamide whereas U.S. Pat. No.5,601,811 (1997) describes about cationic photofilters based oncinnamidoalkyl moiety for UV absorption that are water-soluble. Highwater-solubility is not always desirable for skin care applications dueto possible toxic effects associated with long term usage of cosmeticson human skin. In terms of substantivity to the substrates like skin andhair, water-insoluble cationic photofilters were found to have superiorsubstantivity when compared with water-soluble photofilters in rinse-offproducts.

[0006] The main object of the present invention is therefore tosynthesise hydrophobic molecules containing most popular cinnamidomoiety to provide UV-B absorption and with cationic centre to providesubstantivity to skin, hair and fabric and a long alkyl chain to impartconditioning effect.

SUMMARY OF THE INVENTION

[0007] Thus the present invention provides a novel, substantive,organic-soluble cinnamidoalkylamine quaternary compounds of Formula I,

[0008] wherein

[0009] R₁ is selected from H, halo, —OH, —NH₂, —NO₂, —OCH₃, —N(CH₃)₂,alkyl groups containing from 1 to 6 carbon atoms, alkoxy groupscontaining from 1 to 6 carbon atoms, alkylamino or N,N-dialkylaminogroups containing from 1 to 6 carbon atoms;

[0010] R₂ is selected from hydrogen, alkyl group containing from 1 to 12carbon atoms;

[0011] R₃ and R₄ are independently selected from benzyl, alkyl groupcontaining from 1 to 12 carbon atoms,

[0012] n is an integer from 1 to 6;

[0013] R₅ is selected from an alkyl group containing from 8 to 22 carbonatoms; alkenyl groups containing from 8 to 22 carbon atoms;

[0014] R₇ is selected from bromo, chloro, nitro, methyl and ethylgroups.

[0015] A preferred compound of Formula I is, p-methoxy cinnamidopropyldimethyllauryl ammonium tosylate, wherein, R₁=—OCH₃; R₂=—H; R₃,R₄=CH₃;n=3; R₅=—Cl₁₂H₂₅; R₇=—CH₃ is described.

[0016] In another aspect the invention relates to a process of making aquaternary ammonium salt of cinnamidoalkylamine Formula I,

[0017] wherein

[0018] R₁ is a substituent, selected from H, halo, —OH, —NH₂, —NO₂,—OCH₃, —N(CH₃)₂, alkyl groups containing from 1 to 6 carbon atoms,alkoxy groups containing from 1 to 6 carbon atoms, alkylamino orN,N-dialkylamino groups containing from 1 to 6 carbon atoms;

[0019] R₂ is selected from hydrogen, alkyl group containing from 1 to 12carbon atoms;

[0020] R₃ and R₄ are independently selected from benzyl, alkyl groupcontaining from 1 to 12 carbon atoms,

[0021] n is an integer from 1 to 6;

[0022] R₅ is selected from an alkyl group containing from 8 to 22 carbonatoms; alkenyl groups containing from 8 to 22 carbon atoms;

[0023] R₇ is selected from bromo, chloro, nitro, methyl and ethylgroups,

[0024] wherein the process a compound of Formula II is reacted with acompound of Formula III to give an intermediate of Formula IV, theintermediate of formula IV is quaternised with a compound of Formula V,wherein, R₁, R₂, R₃, R₄, R₅, R₇, n are same as in Formula I and R₆ ofFormula II is selected form —OH, Cl⁻ or —O(CH₂)_(p)CH₃ with p=0 to 3 toprovide the compound of formula I.

[0025] According to a further aspect of the present invention there isprovided skin care, hair care and fabric care formulations containingnovel organic-soluble cinnamidoalkylamine quaternary ammonium compoundsof Formula I and conventional active ingredients of skin and hair careproducts.

[0026] The unique combination of substantivity to hair and skin,conditioning, strong UV absorption and water-insolubility of thesequaternary compounds of cinnamidoalkylamines is very desirable forpersonal care products, especially for skin care applications.

DETAILED DESCRIPTION OF THE INVENTION

[0027] The substantive UV absorbing compounds of the present inventionare quaternary salts of cinnamidoalkylamines that are prepared byreacting lower alkyl ester of cinnamic acid or acid halides of cinnamicacid with an amino compound that is subsequently quaternised withsubstituted benzene sulphonate esters of fatty alcohols. The preferredcompounds of the present invention are water-insoluble quaternaries ofcinnamidoalkylamines.

[0028] In the process, the amidification reaction between a compound ofthe Formula II when R₆=—OH or —O(CH₂)_(p)CH₃ with p=0 to 3, with that ofFormula III is carried out at from about 120° C. to about 200° C., underpressure from about 10 psi to about 100 psi, in the presence of a basiccatalyst such as sodium methoxide, sodium hydroxide from 0.25% to 5.0%by weight of the reaction mass, to afford the intermediate compound ofFormula IV.

[0029] Preferred amount of such catalyst is 1.0% w/w of total reactionmass. The reaction is conveniently monitored by TLC or HPLC using UVdetection. After the complete disappearance of cinnamic acid ester, theexcess diamine is distilled off under vacuum.

[0030] Alternately, this reaction is carried out in the presence of abasic catalyst such as sodium methoxide, sodium hydroxide from 0.25% to5.0% by weight of the reaction mass under atmospheric pressure, underblanket of nitrogen, with an arrangement for continuous selectiveremoval of lower alcohol formed in the reaction.

[0031] Thus, the condensation reaction of one mole of cinnamic acidester is carried with 1.0 to 3.0 moles of diamine at 120 to 200° C.,preferably at 180° C., for 12 to 36 hours. The amines themselves cancatalyse the reaction, however, the rates are found to be slower ascompared with the bases like sodium methoxide and the like.

[0032] The same reaction can be performed using cinnamic acid in placeof cinnamic acid ester at temperatures up to 200° C. and pressures of100 psi, keeping the same stoichiometry (1:1.0 to 3). The excess diamineserves as solvent for the reaction.

[0033] Cinnamic acid esters and amino compounds are selected that areliquid within the disclosed temperature and pressure range. Thisreaction generates lower alcohol that need not be distilled out.

[0034] The amidification reaction between a compound of Formula II whenR₆=—Cl in the presence of a solvent, is carried out with that of FormulaIII at room temperature in the presence of solvent. The compounds ofFormula IV are synthesised by reacting acid chlorides of Formula II (1.0mole) when R₆ is —Cl with the diamines of Formula III (1.0 to 1.2 mole)at 20-50° C. in an inert solvent like dichloromethane, ethylenedichloride, tetrahydrofuran and the like.

[0035] The alkylating agents used in the present invention are fattyalcohol esters of substituted benzene sulphonic acids of Formula V,wherein, R₅ and R₇ are same as in Formula I. Compounds of Formula V aresynthesised from fatty alcohols, either pure or a mixture, by reactingwith benzene sulphonyl chloride or tosyl chloride and the like in thepresence of a suitable base. This esterification is carried out inaprotic solvents like tetrahydrofuran, dichloromethane. Fatty alcoholsused in the present invention are of natural origin (vegetable oils) andsynthetic origin (Ziegler, Oxo process). Thus, they are both branched orstraight chain alcohols, n-octanol, n-dodecanol and the like. The longchain alcohols with a degree of unsaturation like oleyl alcohol are alsosuitable for the present invention.

[0036] Quaternization of cinnamidoamines is carried out in solvents thatinclude, dimethyl formamide, tetrahydrofuran, lower branched alkanolssuch as isopropanol, t-butanol and combinations thereof. Mixtures ofthese solvents can also be used. Solvents used are from 20 to 80% byweight of the reaction mass. The cinnamidoalkylamines (Formula IV, 1mole) are N-alkylated with quaternising agents (Formula V, 1.0 mole) inthe presence of suitable solvents preferably such as THF, isopropanolthat govern temperatures at which the reaction is carried out.

[0037] The quaternisation reaction can be conveniently done in apressure reactor as well as in an open system. The temperatures suitablefor pressure reaction range from about 60-125° C. with the pressures upto 50 psi. The pressures are governed by the amount of solvent and thetemperature selected for the reaction. The conditions of reaction in anopen vessel also get dictated by the choice of solvent. The reactionsare usually carried out at boiling point or slightly below boiling pointof the solvent employed. The resulting quaternary salts are obtained asconcentrated solutions. The progress of the reaction is monitored bymeasuring the amount of unreacted alkylating agent by chromatography orby estimation of unquaternized amidoamine or by determining the activematter (the quaternised product) by two phase titration with anionicsurfactant.

[0038] On Quaternization, the solvents are removed from concentratedsolutions of quaternary ammonium salts to obtain solvent free purecompounds in the form of low melting solids.

[0039] Alternately, quaternisations can be carried out by directlyreacting equimolar quantities of cinnamidoalkylamines of Formula IV withfatty alcohol esters of substituted benzene sulphonic acids of Formula Vat from about 100 to 140° C. for 4 to 24 hours without any solvent andin an inert atmosphere of nitrogen.

[0040] In these cationic compounds as shown in Formula I, the benzenering of cinnamidoalkylamine contains a substituent (R₁), preferably inpara position and is selected from moieties such as —halo, —OH, —NH₂,—NO₂, —OCH₃, —N(CH₃)₂.

[0041] Referring again to Formula I, the amido nitrogen is preferablyeither unsubstituted (R₂ is hydrogen) or may contain a substituent,depicted in Formula I when R₂ is selected from alkyl groups containingfrom 1 to 12 carbon atoms.

[0042] The quaternized nitrogen of compounds in accordance with thepresent invention contains substituents, R₃ and R₄ as depicted inFormula I, same or different, preferably selected from benzyl and/oralkyl groups containing from 1 to 12 carbon atoms.

[0043] The compounds of the present invention are cationic photofilterscontaining cinnamidoalkylamines moiety as shown in Formula I, in which nis an integer between 1 and 6, both inclusive. Preferred cationicphotofilters in accordance with the present invention are compoundscontaining cinnamidoalkylamines in which n is 3.

[0044] The compounds of the present invention are cationic quaternaryammonium salts having cinnamidoalkylamines as shown in Formula I, inwhich the quaternary nitrogen bears the fourth group R₅ that can be afatty alkyl group containing from 8 to 22 carbons, both inclusive, andthe alkyl chain can have unsaturation or branching.

[0045] Thus, the cationic photofilters of the present invention areformed by quaternising compounds of Formula IV by fatty alcohol estersof substituted benzene sulphonic acids of Formula V. The cationicphotofilters of the present invention, also include an anion derivedfrom quaternisation reactions. Given the quaternizing agents describedabove, the cationic compounds of the present invention will contain ananion, benzene sulphonate of Formula I, wherein, R₇ is selected frombromo, chloro, nitro and methyl groups.

[0046] Another embodiment of the present invention relates tomanufacture of a compound of Formula I, in which R₁=para —OCH₃, R₂=—H,R₃=R₄=—CH₃, R₅=—Cl₁₂H₂₅ to —C₁₈H₃₇, R₇=—CH₃, counter anion=tosylateanion and n=3, from the compounds of Formula II (p-methoxy ethylcinnamate, R₁=—OCH₃, R₆=—OC₂H₅), Formula III (N,N-dimethylpropyldiamine,R₂=—H, R₃=R₄=—CH₃, n=3) forming an intermediate compound of Formula IV(p-methoxy cinnamidopropyldimethyl amine, R₁=—OCH₃, R₂=—H, R₃ andR₄=—CH₃) and Formula V (alkyl tosylate, R₅=—C₁₂H₂₅ to —C₁₈H₃₇, R₇=—CH₃).The process of preparation of one such compound of Formula I is given inExample I.

[0047] Another embodiment of the present invention relates tomanufacture of a compound of Formula I, in which R₁=para —OCH₃, R₂=—H,R₃=R₄=—CH₃, R₅=—C₁₂H₂₅ to —C₁₈H₃₇, R₇=—CH₃, counter anion=tosylate anionand n=3, from the compounds of Formula II (p-methoxy cinnamoyl chloride,R₁=OCH₃, R₆=Cl), Formula III (N,N-dimethylpropyldiamine, R₂=—H,R₃=R₄=—CH₃, n=3) forming an intermediate compound of Formula IV(p-methoxy cinnamidopropyldimethyl amine, R₁=—OCH₃, R₂=—H, R₃ andR₄=—CH₃) and Formula V (alkyl tosylate, R₅=—C₁₂H₂₅ to —Cl₁₈H₃₇,R₇=—CH₃). The process of preparation of one such compound of Formula Iis given in Example II.

[0048] The compounds of Formula I with substituents given in above twoparagraphs are soluble in alcohols, glycols, mixtures thereof, mixturesof alcohols and water and mixtures of glycols and water. However, theyare practically insoluble in water alone. Other suitable solvents can bepolyethoxylated triglycerides, polyethoxylated fatty alcohols orethoxylated silicones. These compounds are white to pale yellow solidswith faint fatty odour. The substantive UV-B absorbers of the presentinvention are non-hydrolysable, non-irritant, non-mutagenic andcompatible with commonly used cosmetic ingredients.

[0049] This invention provides compositions containing quaternaryammonium compounds of Formula I that are organic-soluble, UV-absorbing,conditioning and substantive to skin, hair and textile fibres. The haircare and skin care compositions containing compounds of Formula I can besolutions, dispersions or emulsions.

[0050] Lotions may be formed using compounds of Formula I, with orwithout one or more of the inert solvents like ethyl alcohol, isopropylalcohol or propylene glycol, by combining with film forming polymerslike proteins, polyvinyl pyrrolidone, polyvinyl alcohols and the like,film-forming starches and resins and the like.

[0051] Oil-in-water and water-in-oil emulsion can also be employed asvehicles for these compounds of Formula I to form lotions and creams.Conventional oil soluble UV-absorbing compounds like cinnamates,salicylates, p-aminobenzoates, benzophenones can be dissolved in oilyphase of emulsion/lotions. The water-soluble sunscreens are dissolved inan aqueous phase of the emulsion and combined with the oily phase usinga suitable cationic emulsifier such as stearylkonium chloride. Vegetableor mineral oils suitable for use as oil phase include mineral oil,petroleum, castor oil, sesame oil and the like. The quaternary ammoniumcompounds of the present invention are added to oily phase which is thensubsequently emulsified with aqueous phase using an emulsifier likestearylkonium chloride or non-ionic emulsifiers like polysorbate-80,fatty alcohol ethoxylates and the like.

[0052] A preparation of cream hair conditioner of emulsion type havingsunscreens of both the types, organic-soluble compounds of Formula I andwater-soluble (organic-insoluble) sunscreens of our co-pending patentapplication (Indian Patent Appl. No. 903/Mum/2000 dated Oct. 6, 2000) isgiven in Example IV.

[0053] Perfumes, fragrances, anti-oxidants, preservatives, dyescolorants, insect repellents, fillers and suspended particulate matter,emollients, humectants, thickeners and the like may optionally beincluded in the sunscreen and tanning compositions of the presentinvention.

[0054] The sunscreen and tanning compositions of the present inventioncontain an effective amount of compounds of Formula I to preventerythema. In general, an amount of about 0.5% to 10% w/w of the totalcomposition is used.

[0055] For everyday use a sunscreen cream to protect the skin from bothUV-A and UV-B radiation can be formulated as given in Example VI. Thesubstantive UV absorbers, both water-soluble (β,β′-di(p-methoxycinnamidopropyldimethyl ammonium chloride)ethyl ether) andwater-insoluble (compounds of Formula I) can be convenientlyincorporated at 2.0% each w/w of total composition. To cover UV-A rangebutyl methoxy dibenzoyl methane (Parsol 1789) is incorporated.

[0056] Face powder compositions of the present invention containcompounds of Formula I in an effective amount of 0.1% w/w to 0.5% w/w.

[0057] The hair care and skin care compositions of the present inventioncontaining compounds of Formula I and may contain one or moreingredients selected form cosmetic agents such as surfactants, othersunscreen chemicals, after sun treatment materials, emollients,humectants, perfumes, anti-perspirants, moisturisers, color cosmeticmaterials, herbal extracts, occlusive oils and essential oils.

[0058] The compositions of compound with Formula I provide hairprotection from UV radiation in addition to good conditioning effect.The hair protecting preparations can be formulated in the form ofcreams, lotions, tonics or gels.

[0059] The compounds of the present invention may also be formulated ashair care product such as shampoos, cream rinses, hair conditioners,hair dressing preparations, hair relaxers, hair coloring products andthe like, capable of protecting hair from UV-B radiation.

[0060] The rinse-off preparations like shampoos, face washes and bathingbars contain 0.5 to 10% w/w of compounds of Formula I. It may be notedthat these quaternaries are compatible with usual anti-dandruff,anti-microbial agents like Zinc pyrithione, Irgasan, Pyroctone. Hence,these compounds of Formula I can be incorporated in anti-dandruffshampoos.

[0061] Despite their cationic nature, the compounds of Formula I arecompletely compatible with anionic surfactants like sodium lauryl ethersulphate. The water insolubility and cationic nature does not effecttransparency of transparent shampoo. The shampoo formulation thus madehas been shown to deposit the quaternary compounds on hair (ExampleIII).

[0062] Soap bars, both opaque and transparent/translucent can beformulated with compounds of UV-absorbing and conditioning compounds ofFormula I. In soap bars, the cinnamidoalkyl quaternary ammoniumcompounds can be incorporated from 0.5 to 10.0% w/w, more preferablyfrom 1.0 to 2.0% w/w of total composition. It may be noted that thecompounds of Formula I in the following combi-bar formulation arecompatible with anionic surfactants.

[0063] Furthermore, the compounds of Formula I when incorporated into atypical detergent powder or other household cleaning productcompositions based on phosphate, carbonate or zeolite builders, veryeffectively impart anti-fading effect to colored fabric because of theirsubstantivity. Typical detergent and household cleaning productcompositions in accordance with the present invention include one ormore surfactants, selected from anionic, cationic, nonionic andamphoteric detergents, alone or in combination. A typical detergentpowder has been shown to deposit cationic photofilters of the presentinvention on fabric (Example VII).

[0064] The hair and skin protecting and detergent and household cleaningcompositions of the present invention are also formed by admixing,dissolving the compounds of Formula I with other ingredients as inrespective conventional composition. The preferred cosmetic compositionsare solutions, dispersions or emulsions. The compositions contain aneffective amount of one or more of UV-absorbing and conditioningcompounds of the present invention to prevent erythema and darkening ofskin due to solar damage.

[0065] In general, an amount of compounds of Formula I of about 0.5% toabout 10% w/w and preferably between 2.5 to 8.0% w/w in a cosmeticcomposition of compounds of Formula I is useful particularly in personalhair and skin care products, sunscreens and tanning lotions. Leave-onpreparations like hair oil may contain 0.01% to 2.0% w/w of compounds ofFormula I. Typically, the ingredients are combined with mixing andheating if necessary until a uniform, homogeneous product is formed.With respect to the emulsion products of the present invention, thewater-soluble and water-insoluble ingredients are mixed separately andcombined with suitable emulsifier, preferably a cationic emulsifier, toform an emulsion.

[0066] A sunscreen cream for everyday use can be formulated with bothwater-soluble UV-B absorber (β,β′-di(p-methoxy cinnamidopropyldimethylammonium chloride)ethyl ether, Indian Patent Appln. No. 903/Mum/2000)and water-insoluble UV-B absorbers (compounds of Formula I) and anyeffective UV-A absorber like Parsol-1789 with silicone conditioners andVitamins meant for skin care.

[0067] Unlike the hydrophobic photofilters from the prior art that arePABA based, the organic-soluble quaternary ammonium compounds of thepresent invention are based on cinnamidoalkyl moiety and absorb verystrongly in UV-B region (e.g. molar extinction coefficient, ε ofp-methoxy cinnamidopropyldimethyllauryl ammonium tosylate was found tobe 25,000 at λmax 310 nm). The cationic centre provides substantivity toskin, hair and fabric and the long alkyl chain provides thesoftening/conditioning effect.

[0068] The water insolubility and substantivity makes these moleculesextremely attractive for external applications as against water-solublemolecules that may get absorbed through skin. In addition to theseadvantages, the compounds of the present invention are compatible withall commonly used cosmetic ingredients and are extremely stable. Despitebeing cationic surfactants, the compounds of the present invention arecompatible with anionic surfactants and can be conveniently included ina transparent shampoo or a transparent bathing bar.

EXAMPLES

[0069] The invention will now be illustrated with the help of examples,Examples I and II for process of manufacture of compounds of Formula Iand Examples III to VII for compositions. The examples are by way ofillustrations only and in no way restrict the scope of invention. Manychanges and modifications can be made within the scope of the presentinvention without departing from the spirit thereof and the inventionincludes all such modifications. A few formula variations for thepreparation of shampoo, cream hair conditioner, transparent bathing bar,sunscreen cream and detergent powder with compounds of Formula I areillustrated in Examples III, IV, V, VI and VII respectively.

Example I

[0070] Process for Preparation p-methoxy CinnamidopropyldimethyllaurylAmmonium Tosylate:

[0071] The compound of Formula I, wherein, R₁=—OCH₃; R₂=—H; R₃,R₄=CH₃;n=3; R₅=—C₁₂H₂₅; R₇=—CH₃ from ethyl-methoxy cinnamate.

[0072] Fatty alcohols were obtained from Henkel A. G.N,N-dimethylpropyldiamine and p-toluene sulphonyl chloride was obtainedfrom BASF and Gayatri Chemicals respectively. Ethyl p-methoxy cinnamatewas supplied by Galaxy Surfactants Ltd.

[0073] p-Methoxy cinnamidopropyldimethylamine was synthesised from ethylp-methoxy cinnamate and N,N-dimethylpropyldiamine.

[0074] a) Preparation of p-methoxy Cinnamidopropyldimethylamine:

[0075] Ethyl p-methoxy cinnamate (206.0 g, 1.0 mole),N,N-dimethylpropyldiamine (306.0 g, 3.0 mole) and sodium methoxide (2.0g) were charged in a pressure reactor. The air inside the reactor wasflushed out by purging of nitrogen. The reaction mixture was thenstirred at 180° C. (this generated pressure of 18 kg/cm²) for 36 hours.The progress of reaction was monitored by disappearance of ethylp-methoxy cinnamate on chromatography (TLC and HPLC). The TLC wasperformed on aluminium coated silica gel plates (Merck-60-F-254) andviewed with a UV lamp at 254 nm. HPLC was performed using reversed phasetechnique on a C-18 bonded (octadecyl silane) column and 60% aqueousmethanol as mobile phase (1.0 ml/min) and detection at 280 nm. Theexcess amine was removed under vacuum. The golden yellow solid (263.0 g)thus obtained had amine value of 245. Molar extinction coefficient, ε,in methanol was found to be 24,224 at 290 nm.

[0076] IR in dichloromethane showed carbonyl stretching of amide at 1660cm⁻¹ and NH stretching at 3300 cm⁻¹. ¹H NMR (300 MHz, CDCl₃): δ1.73 (p,2H, J=6.6 Hz), 2.26 (s, 6H), 2.42 (t, 2H, J=6.6 Hz), 3.45 (q, 2H, J=6.0Hz), 3.81 (s, 3H), 6.27 (d, 1H, J=15.6 Hz), 6.86 (d, 2H, J=8.7 Hz), 7.43(d, 2H, J =8.7 Hz), 7.53 (d, 1H, J =15.6 Hz).

[0077] b) Preparation of Lauryl Tosylate:

[0078] To a stirred and a cooled solution of lauryl alcohol (186.0 g,1.0 mole) and triethyl amine (121.0 g, 1.2 mole) in dichloromethane (600ml), p-toluene sulphonyl chloride (228.0 g, 1.2 mole) in dichloromethane(400 ml) was slowly added and the reaction was continued at roomtemperature for 10 hours. The reaction mixture was then washed with 20%sodium chloride solution (500 ml). The washed organic layer was driedover anhydrous sodium sulphate. Removal of solvent under vacuo resultedin colorless oil that solidified on keeping to yield lauryl tosylate.(309.0 g, 91%), m. p. 29° C. (literature m. p. 29° C.).

[0079] c) Preparation of p-methoxy CinnamidopropyldimethyllaurylAmmonium Tosylate:

[0080] A mixture of lauryl tosylate (306.0 g, 0.9 mole) and p-methoxycinnamidopropyldimethyl amine (235.8 g, 0.9 mole) was stirred underblanket of nitrogen at 110° C. for 20 hours. The progress of reactionwas monitored by estimation of unquaternised amine. On cooling, thereaction yielded pale yellow solid that was crystallised fromisopropanol to give quaternary ammonium compound as white solid (501.0g) with m. p. 130-135° C.

[0081] IR (CH₂Cl₂): 1656 cm⁻¹ carbonyl of amide.

[0082]¹H NMR (CDCl₃, 300 MHz): δ0.87 (3H, t, J=6.3 Hz), 1.18 (18H, broadsignal), 1.58 (2H, unresolved multiplet), 2.10 (2H, unresolvedmultiplet), 2.32 (3H, singlet, methyl of tosyl), 3.13 (6H, singlet, twomethyl on nitrogen), 3.20 (2H, unresolved multiplet), 3.45 (2H,unresolved multiplet), 3.68 (2H, unresolved multiplet), 3.78 (3H,singlet, OCH₃), 6.52 (1H, d, J=15.6 Hz), 6.76 (2H, d, J=8.4 Hz), 7.14(2H, d, J =6.0 Hz), 7.31 (2H, d, J=8.6 Hz), 7.48 (1H, d, J=15.6 Hz),7.78 (2H, d, J=7.8 Hz).

[0083] The molar extinction coefficient, ε was found to be 25,000 atλmax 310 nm in methanol.

[0084] The final compound was analysed on HPLC using ion-pairingtechnique. The mobile phase employed for ion-pairing comprised of 0.1 Moctane sulphonic acid in aqueous methanol (70:30). Reversed phase columnChromspher C8 was used with mobile phase flow rate of 1.0 ml/min. Thedetection was done at 280 nm. The retention time for p-methoxycinnamidopropyldimethyllaurylamine was found to be 10.0 minutes.

[0085] The purity of final compound from this analysis was found to be98.0% with 2.0% unquaternised amine.

Example II

[0086] Process for Preparation p-methoxy CinnamidopropyldimethyllaurylAmmonium Tosylate:

[0087] The compound of Formula I, wherein, R₁=—OCH₃; R₂=—H; R₃,R₄=CH₃;n=3; R₅=—C₁₂H₂₅; R₇=—CH₃ from-methoxy cinnamoyl chloride. p-Methoxycinnamidopropyldimethylamine was synthesised from p-methoxy cinnamoylchloride and N,N-dimethylpropyldiamine.

[0088] (a) Preparation of p-methoxy Cinnamoyl Chloride:

[0089] To a stirred suspension of p-methoxy cinnamic acid (178.0 g, 1.0mole) in dichloromethane (500 ml), thionyl chloride (238.0 g, 2.0 moles)was added slowly and the reaction mass was heated at 45° C. for 3 hours.The excess of thionyl chloride was removed under vacuum and the-methoxycinnamoyl chloride was distilled (145° C./0.2 mm) in 85% yield ascolourless solid with m. p. 50° C. (Literature m.p. 50° C., Dictionaryof Organic Compounds, Chapmann and Hall, 1994).

[0090] (b) Preparation of p-methoxy Cinnamidopropyldimethylamine:

[0091] To a stirred solution of N,N-dimethylpropyldiamine (102.0 g, 1.0mole) in dichloromethane (500 ml), solution of p-methoxy cinnamoylchloride (196.0 g, 1.0 mole) in dichloromethane from step (a) was slowlyadded and the reaction was continued at room temperature for 2 hours.The reaction mixture in dichloromethane was washed with aqueous sodiumhydroxide (200 ml, 20.0%). The organic layer was dried over anhydroussodium sulphate. The removal of solvent using a rotary evaporatorafforded the p-methoxy cinnamidopropyldimethylamine (235.0 g) ascolourless solid, m.p. 80° C. Reversed phase HPLC showed it to be 98%pure with amine value 217.

[0092] The NMR, IR and HPLC data matched with the data for the compoundobtained in Example I.

[0093] (c) Preparation of Lauryl Tosylate

[0094] Lauryl tosylate was synthesised as per step (b) of Example I.

[0095] (d) Preparation of p-methoxy CinnamidopropyldimethyllaurylAmmonium Tosylate:

[0096] A mixture of lauryl tosylate (153.0 g, 0.45 mole), p-methoxycinnamidopropyldimethyl amine (118.0 g, 0.45 mole) and isopropanol (270ml) was refluxed under blanket of nitrogen at 85° C. for 48 hours.Isopropanol was removed on a rotary evaporator using temperature andvacuum. The NMR, melting point of solid quaternary ammonium compoundthus obtained matched with that of Example I.

[0097] The purity of final compound from this analysis was found to be97.2% with 1.8% unquaternised amine by ion pairing HPLC.

Example III

[0098] Preparation of Transparent Shampoo

[0099] A transparent shampoo was formulated using p-methoxycinnamidopropyldimethyllauryl ammonium tosylate prepared as in ExampleI. The other active ingredients, SLES-2, Sodium lauryl ether sulphate,an anionic surfactant, 30% aqueous solution, CAPB, Cocoamidopropylbetaine, an amphoteric surfactant, 30% aqueous solution and Galsilk,Polyquaternium-7 were obtained from Galaxy Surfactants Ltd., Mumbai,India. Methyl paraben and propyl paraben were obtained from GayatriLaboratories, Mumbai, India. Approved fragrances and colors wereobtained from S. H. Kelkar & Co., Mumbai, India and Koel Colors Pvt.Ltd., Mumbai, India respectively.

[0100] A shampoo composition containing p-methoxycinnamidopropyldimethyllauryl ammonium tosylate of Example I wasprepared in accordance with the optimum formulation given below.Acceptable formula variations for the preparation of such shampoo arealso illustrated. Range Preferred Optimum Ingredient % (w/w) % (w/w) %(w/w) SLES-2 (30%) 40-60 45-60 50.00 CAPB (30%)  1-10  2-10 8.00p-methoxy cinnamidopropyl 0.5-10  2-5 2.00 dimethyllauryl ammoniumtosylate Galsilk  3-10 4-6 5.00 Sodium chloride Quantity sufficientPreservatives/colour and fragrance/ Quantity sufficient chelating agentsDeionised water Quantity sufficient to make 100%

[0101] The Transparent Shampoo was Prepared as Follows:

[0102] The ingredients were mixed with heating to 50° C. until a uniformhomogenous mixture was formed. The resulting mixture was then cooled toroom temperature with continuous stirring. The required chelating agent,colour, perfume were added. The viscosity was adjusted to 2500 cps withsodium chloride.

[0103] The p-methoxy cinnamidopropyldimethyllauryl ammonium tosylate wasfound to be completely compatible with anionic surfactant. Thesubstantivity experiment was performed as described under;

[0104] Virgin hair (5.0 g) were washed with 10% SLES solution and rinsedwith plain water. The tresses were treated for exactly 5.0 minutes withclear shampoo (containing 2% p-methoxy cinnamidopropyldimethyllaurylammonium tosylate) as described in Example I that was diluted five timeswith water. After the treatment the tresses were washed thoroughly withcopious amount of water. The adsorbed quaternary was extracted from thehair surface by immersing each tress in isopropanol at 65° C. for 30minutes. A known volume of this isopropanol/quaternary ammonium saltmixture was analysed by UV-spectroscopy to determine its absorptionintensity.

[0105] The substantivity was found to be 37 mg/100 g of hair.

Example IV

[0106] Preparation of cream hair conditioner

[0107] Cetyltrimethylammonium chloride was obtained from FlamePharmaceuticals Pvt. Ltd., Mumbai, India, Isopropyl myristate wasobtained from Anusynth Chemical Industries, Mumbai, India, Lanoline wasobtained from Rolex Lanoline Products Ltd., Mumbai, India.Phenoxyethanol and β,β′-di(p-methoxy cinnamidopropyldimethyl ammoniumchloride)ethyl ether (a water-soluble cationic UV-B sunscreen, IndianPatent Appln. No. 903/Mum/2000) were obtained from Galaxy SurfactantsLtd., Mumbai, India.

[0108] A cream hair conditioner containing p-methoxycinnamidopropyldimethyllauryl ammonium tosylate of Example I wasprepared in accordance with the optimum formulation given below.Acceptable formula variations for the preparation of such cream hairconditioner are also illustrated. Range Preferred Optimum Ingredient %(w/w) % (w/w) % (w/w) p-methoxy cinnamidopropyl 0.5-5   1-3 2.0dimethyllauryl ammonium tosylate β,β′-di(p-methoxy cinnamidopropyl0.5-5   1-3 2.0 dimethyl ammonium chloride)ethyl Cocoamidopropyl betaine1-6 0.5-2   0.5 Cetyl trimethyl ammonium chloride  1-15  4-10 4.5Cetostearyl alcohol  1-15  5-10 5.5 Lanoline 0.5-10  1-5 1.5 Isopropylmyristate 0.5-5   1-3 1.0 Chelating agents/preservatives/ Quantitysufficient fragrances Deionised water Quantity sufficient to make 100%

[0109] The cream hair conditioner was prepared as follows:

[0110] Aqueous phase containing cetyltrimethylammonium chloride,cocoamidopropyl betaine, β,β′-di(p-methoxy cinnamidopropyldimethylammonium chloride)ethyl ether and water were stirred together at 70° C.Oily phase comprising cetostearyl alcohol, isopropyl myristate,lanoline, p-methoxy cinnamidopropyldimethyllauryl ammonium tosylate andpreservatives was maintained at 70° C. under stirring. The oily phase isslowly added to the stirred aqueous phase at 70° C. and the wholemixture was cooled under vigorous stirring to 40° C. Perfume and otheradditives were added and continued cooling under stirring to get goodcream.

Example V

[0111] Preparation of Transparent Bathing Bar

[0112] A transparent bathing bar containing p-methoxycinnamidopropyldimethyllauryl ammonium tosylate of Example I wasprepared in accordance with the optimum formulation given below.Acceptable formula variations for the preparation of such transparentbathing bar are also illustrated. Range Preferred Optimum Ingredient %(w/w) % (w/w) % (w/w) (30%) 10-50 20-35 28 B (30%)  5-30 10-20 16 umcocoate  5-20 10-15 9.0 um stearate 15-70 15-20 13.8 ylene Glycol 10-3010-25 20 itol (70%)  4-15  8-10 8.0 thoxy cinnamidopropyl 0.5-10 1.0-5.0 2.0 thyllauryl ammonium tosylate ating agent/colour and Quantitysufficient ance/ nised water Quantity sufficient to make 100%

[0113] The transparent bathing bar was prepared as follows:

[0114] All ingredients were heated together under stirring to 70° C.till the reaction mass became homogenous and transparent. The reactionmass was cooled to 40° C. and the required amounts of perfume and colourwere added. The molten mass was cast in moulds of desired shape to yieldtransparent bathing bar. It could be easily seen that the transparencyof bathing bar was unaffected proving the total compatibility ofp-methoxy cinnamidopropyldimethyllauryl ammonium tosylate with anionicsurfactant. The transparent bar thus made was evaluated as per theprocedure described in Example III and the substantivity was found to be29 mg/100 g of hair.

Example VI

[0115] Preparation of Sunscreen Cream

[0116] Parsol—1789 was procurred from Givaudan, Roure, USA. Tween-80,Niacinamide and Vitamin E acetate were obtained from S. D. Fine Chem.,Mumbai, India. Lauryl alcohol ethoxylate, ethylene glycol monostearate,glyceryl monostearate were obtained from Galaxy Surfactants Ltd.,Mumbai, India. Dimethicone copolyol (SF 1188A) was obtained from GeneralElectric, Bangalore, India.

[0117] A sunscreen cream for every day use containing p-methoxycinnamidopropyldimethyllauryl ammnonium tosylate of Example I wasprepared in accordance with the optimum formulation given below.Acceptable formula variations for the preparation of such sunscreencream are also illustrated. Range Preferred Optimum Ingredient % (w/w) %(w/w) % (w/w) ethoxy cinnamidopropyl dimethyl- 1-10 1-5 2.0 laurylnonium tosylate -di(p-methoxy cinnamidopropyl- 1-10 1-5 1.0 dimethylnonium chloride)ethyl ether ol-1789 (UV-A filter) 1-5  1-3 1.0sorbate-80 (Tween-80) 1-12 3-7 5.0 yl alcohol ethoxylate -9 EO 1-12 3-75.0 id paraffin oil 1-12 3-7 5.0 ropyl myristate 1-12 3-7 5.0 leneglycol monostearate 1-12 3-7 5.0 eryl monostearate 1-12 3-7 5.0 stearylalcohol 1-12 3-7 5.0 Dimethicone copolyol 1-10 2-3 2.0 Vitamin E acetate0.5-5   1-3 0.5 Niacinamide 0.5-5   1-3 1.0 Hydroguinone 0.5-3   1-2 1.0Sodium sulphite 0.1-1   0.1-0.5 0.2 Preservatives/fragrance Quantitysufficient Deionised water Quantity sufficient to make 100%

[0118] The Sunscreen Cream was Prepared as Follows:

[0119] Aqueous phase containing β,β′-di(p-methoxycinnamidopropyldimethyl ammonium chloride)ethyl ether, Tween-80, laurylalcohol ethoxylate—9 EO, sodium sulphite, dimethicone copolyol and waterwas stirred at 70° C. The oily phase comprising of p-methoxycinnamidopropyl dimethyllauryl ammonium tosylate, isopropyl myristate,paraffin oil, glyceryl monostearate, ethylene glycol monostearate,Vitamin E acetate, cetostearyl alcohol, niacinamide, hydroquinone andthe preservatives was heated under stirring to 70° C. The oily phase isthen added to the vigorously stirred aqueous phase and cooled understirring to 40° C. At this stage fragrances were added and cooled understirring to room temperature to get a good shiny cream.

Example VII

[0120] Preparation of Detergent Powder

[0121] Linear alkyl benzene sulphonic acid was obtained from Albrightand Wilson Chemicals (India) Ltd., Mumbai, India.

[0122] A detergent powder containing p-methoxycinnamidopropyldimethyllauryl ammonium tosylate of Example II wasprepared in accordance with the optimum formulation given below.Acceptable formula variations for the preparation of such detergentpowder are also illustrated. Range Preferred Optimum Ingredient % (w/w)% (w/w) % (w/w) Soda ash 20-50 20-30 20 Sodium tripolyphosphate  1-3015-25 25 Sodium alkyl benzene sulphonate 10-50 10-30 20 Sodium chloride 1-45  5-15 5.0 Sodium sulphate  1-40 10-20 20 p-methoxy cinnamidopropyl0.5-10  2-4 4.0 dimethyllauryl ammonium tosylate Sodium carboxy methylcellulose 0.5-5   1-2 1.0 Sodium silicate 1-5 1-2 2.0 Chelatingagent/colour and Quantity sufficient fragrance

[0123] The Detergent Powder was Prepared as Follows:

[0124] To a stirred mixture of soda ash, sodium tripolyphosphate, sodiumchloride and sodium sulphate, linear alkyl benzene sulphonic acid wasslowly added. The mixture was then cooled to room temperature. Otheractive ingredients including sodium carboxy methyl cellulose, sodiumsilicate and p-methoxy cinnamidopropyldimethyllauryl ammonium tosylatewere then added to this mixture along with the other additives likenonionic surfactant, bleaching agent, optical brightener, chelatingagent, colour and perfume and stirring was continued to get uniformdetergent powder.

[0125] The detergent thus made was evaluated for the deposition ofquaternary on cotton fabric (substantivity) as per the principlesdescribed in Example III and was found to be 27 mg/100 g of cottonfabric.

1. A quaternary ammonium salt of cinnamidoalkylamine Formula I,

wherein R₁ is a substituent, selected from H, halo, —OH, —NH₂, —NO₂,—OCH₃, —N(CH₃)₂, alkyl groups containing from 1 to 6 carbon atoms,alkoxy groups containing from 1 to 6 carbon atoms, alkylamino orN,N-dialkylamino groups containing from 1 to 6 carbon atoms; R₂ isselected from hydrogen, alkyl group containing from 1 to 12 carbonatoms; R₃ and R₄ are independently selected from benzyl, alkyl groupcontaining from 1 to 12 carbon atoms, n is an integer from 1 to 6; R₅ isselected from an alkyl group containing from 8 to 22 carbon atoms;alkenyl groups containing from 8 to 22 carbon atoms; R₇ is selected frombromo, chloro, nitro, methyl and ethyl groups:
 2. A quaternary salt ofclaim 1, wherein the compound of formula I is p-methoxycinnamidopropyldimethyllauryl ammonium tosylate, wherein, R₁=para —OCH₃,R₂=—H, R₃=R₄=—CH₃, R₅=—C₁₂H₂₅, n=3 and the counter anion=tosylate anion.3. A process of making a quaternary ammonium salt of cinnamidoalkylamineFormula I,

wherein R₁ is a substituent, selected from H, halo, —OH, —NH₂, —NO₂,—OCH₃, —N(CH₃)₂, alkyl groups containing from 1 to 6 carbon atoms,alkoxy groups containing from 1 to 6 carbon atoms, alkylamino orN,N-dialkylamino groups containing from 1 to 6 carbon atoms; R₂ isselected from hydrogen, alkyl group containing from 1 to 12 carbonatoms; R₃ and R₄ are independently selected from benzyl, alkyl groupcontaining from 1 to 12 carbon atoms, n is an integer from 1 to 6; R₅ isselected from an alkyl group containing from 8 to 22 carbon atoms;alkenyl groups containing from 8 to 22 carbon atoms; R₇ is selected frombromo, chloro, nitro, methyl and ethyl groups, Wherein the process acompound of Formula II is reacted with a compound of Formula III to givean intermediate of Formula IV, the intermediate of formula IV isquaternised with a compound of Formula V, wherein, R₁, R₂, R₃, R₄, R₅,R₇, n are same as in Formula I and R₆ of Formula II is selected form—OH, Cl⁻ or —O(CH₂)_(p)CH₃ with p=0 to 3 to provide the compound offormula I.


4. A composition comprising a cinnamidoalkylamine cationic salt of claim1 and one or more of other ingredients selected from the cosmetic agentssuch as aqueous and oily moisturisers, film forming agents, emulsifiers,thickening agents, skin and hair conditioning agents, vegetable oils,humectants, surfactants, emollients and rheological modifiers.
 5. Thecomposition of claim 4, wherein said one or more of other ingredientscomprise of detergents that are selected from the group consisting ofanionic detergents, cationic detergents, non-ionic detergents andamphoteric detergents.
 6. The composition of claim 4, wherein one ormore of other ingredients are present in an amount about 25% w/w of saidcomposition.
 7. The composition of claim 4, wherein saidcinnamidoalkylamine quaternary salt is present in an amount in the rangefrom about 0.01% to about 10.0% w/w of said composition.
 8. Thecomposition of claim 4, wherein the other ingredients are chosen to givea shampoo formulation.
 9. The composition of claim 4, wherein the otheringredients are chosen to give a hair conditioner formulation.
 10. Thecomposition of claim 4, wherein the other ingredients are chosen to givea bathing bar formulation.
 11. The composition of claim 4, wherein theother ingredients are chosen to give a sunscreen cream formulation. 12.The composition of claim 4, wherein the other ingredients are chosen togive a detergent powder formulation.